Oregon Revised Statutes Public Health and Safety § 459.205

(1) Except as provided by ORS 459.215, a disposal site shall not be established, operated, maintained or substantially altered, expanded or improved, and a change shall not be made in the method or type of disposal at a disposal site, until the person owning or controlling the disposal site obtains a permit therefor from the Department of Environmental Quality as provided in ORS 459.235.

(2) The person who holds or last held the permit issued under subsection (1) of this section, or, if that person fails to comply, then the person owning or controlling a land disposal site that is closed and no longer receiving solid waste must continue or renew the permit required under subsection (1) of this section after the site is closed for the duration of the period in which the department continues to actively supervise the site, even though solid waste is no longer received at the site.